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[11.05] The Origin of UHECRs: The Reconnection of The Free Energy of the Universe

S.A. Colgate, H. Li (LANL)

The energy density of extragalactic CRs would reach nearly 1% of the local CRs if its spectrum is extrapolated back to GeV with the same spectral index \Gamma = -2.6. This implies an energy in CRs per galaxy within the galaxy walls, ~3 \times 10⁵⁹ ergs. The lack of an observed GZK cut-off implies a loss timescale of < 10⁸ yr. This loss must be an energy independent loss to the galaxy voids. In a Hubble time the accelerated CR energy is then > 5 \times 10⁶¹ ergs per galaxy. Only the 10⁸ M_\odot black hole of each galaxy (2 \times 10⁶² ergs) is a potential and feasible energy source. We describe a sequence of physical processes that leads to the formation of massive black holes and how large scale magnetic fields can be produced by an \alpha- \Omega dynamo using star-disk collisions within the accretion disk. As this dynamo saturates, magnetic fields are expelled away from the disk as a force-free helix. These stressed magnetic fluxes eventually populate the IGM and are confined in the galaxy walls by the infall pressure. Part of this magnetic energy will dissipate via reconnection process, from which UHECRs are produced. Another part of it, along with the CRs, escape into the galaxy voids, becoming the dark energy of the universe. (Supported by DOE.)